Brake lights won't work...03 Tacoma

skizman

Member
All 3 brake lights won't come on, but all other lights work. This is what I did.
Replaced the brake light switch...
Replaced tail light relay under hood in fuse box...
Checked and replaced tail and brake light fuses under hood and under dash.
Tried different bulbs...
Checked ground wire under bumper.
Unplugged brake light switch plug and checked with multimeter, checked all contacts with probes and there was no voltage.
Help!!!!!!!!!!! I have no idea what to try next.
Brake lights always work without ignition on. Not now.
 
Ground wire?I also saw on a frontier behind the brake pedal there is a plastic piece that works the brake switch that is on the fire wall behind the brake pedal. See if the taco is rigged up the same way. Just trying to help I’m sure it’s something small
 
Do you have voltage at the switch?
I misread what he wrote too,..... ok, was there voltage in the fuse box? It should if anything does... power at relay? Connections? Find the voltage and trace it. Could be something as silly as a connector rattling loose.
 
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I misread what he wrote too,..... ok, was there voltage in the fuse box? It should if anything does... relay? Connections? Find the voltage and trace it. Could be something as silly as a connector rattling loose.

I’m thinking it has to be something small and stupid we are over looking and over thinking
 
I misread what he wrote too,..... ok, was there voltage in the fuse box? It should if anything does... power at relay? Connections? Find the voltage and trace it. Could be something as silly as a connector rattling loose.
I pulled the relay and crossed a couple terminals with a wire and running lights came on. That's all I could get crossing terminals.
 
Here's a very simple wiring diagram of brake lights, not specific to an 03 tacoma but hopefully this helps. So again, I'll ask, was there power coming into the switch on the pedal? (Separate power source) (find a good grounding point for negative lead, touch positive lead to either terminal on the switch, should get 12v?) Is your meter set to the correct setting? 20180923_082037.jpeg
 
I'm not getting any voltage out of the plug on the brake light switch. I've rechecked the fuses again. I have no choice but to take it to a shop. I've done all I could. Thanks.
Bummer. Let us know what it ends up being.
 
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